On Sat, 5 Sep 2020 13:29:54 +1000
Brian Scott <user-7c0060721e1b@xymon.invalid> wrote:
Hi list,
Has anyone had experience with running the xymon client on the latest
Macos?
My particular problem is that the handling of disk mounts and
capacities has gone seriously weird. First exhibit - output from the
mount command:
# mount
/dev/disk1s1 on / (apfs, local, read-only, journaled)
devfs on /dev (devfs, local, nobrowse)
/dev/disk1s2 on /System/Volumes/Data (apfs, local, journaled,
nobrowse) /dev/disk1s5 on /private/var/vm (apfs, local, journaled,
nobrowse) map auto_home on /System/Volumes/Data/home (autofs,
automounted, nobrowse)
All volumes are either marked nobrowse or read-only so no disks are
selected by xymonclient-darwin.sh. This has the immediate kick on
effect of causing a bash set command to dump all set variables
because the filesystem list is empty. Ignoring this because we
actually want to select some filesystems, the question is which ones.
Looking at the output from df:
# df -P -H
Filesystem????? Size?? Used? Avail Capacity? Mounted on
/dev/disk1s1??? 1.0T??? 11G??? 92G??? 11%??? /
devfs?????????? 345k?? 345k???? 0B?? 100%??? /dev
/dev/disk1s2??? 1.0T?? 893G??? 92G??? 91%??? /System/Volumes/Data
/dev/disk1s5??? 1.0T?? 3.2G??? 92G???? 4%??? /private/var/vm
map auto_home???? 0B???? 0B???? 0B?? 100%??? /System/Volumes/Data/home
It looks like /dev/disk1s1, s2 and s5 are all the same real partition
but account for different space from it, i.e. total size = 1.0T, Used
= 11G+893G+3.2G=907.2G, Avail=92G.
This would suggest that a reasonable thing to monitor would be one of
these entries ('/' makes some sense) and derive used as size-avail
(1.0T-92G).
APFS volumes are more akin to BTRFS subvolumes or ZFS filesystems
than to traditional partitions: the available space on the physical
storage is shared between them on an as-needed basis.
There might be some Apple-specific command line tool to get the
statistics you want, but failing that, you'll need to track which
partitions are APFS versus something else when deciding how to
calculate usage.
--
Mark